Improvement in molding female screws



PLFETERS, PHOTO-LITMDGRAPHER. WASHINGTON C E. L. LAMB AND SAM. VOOD, OFKEOKUK, IOWVA.

IMPROVEMENT IN MOLDING FEMALE SCREWS.

Specification forming part of Letters Patent No. 23, l h`76, dated March8, 1859.

To all whom, it may concer/2,:

Be it known that we, EDWARD L. LAMB and SAMUEL WooD, of Keokuk, -in thecounty of Y Lee and State of Iowa, have invented certain new and usefulImprovements in Molding Female Screws; and we do hereby declare that thefollowing is a full, clear, and exact description of the same, reference`being had to the accompanying drawings, of which- Figure l is aperspeetiveview of amoldingflask with the improvement iu place; Fig. 2,a plan of one-half of the match-plate, (full size;) Fig 3, a section ofthe same at its line of division, (full size;) Fig. 4, section of iiaskwith match-plates in place; Fig. 5, section of mold with match-plateremoved and ready for reception of the metal; Fig.6, plan of flask, copeside up; Fig. 7, plan of flask inverted, or drag side up, Fig. S, planof matchplate, cope side up; Fig. 9, plan of matchplate inverted, ordrag side up.

In the manufacture of east-iron axles or axlearms with screws and nutson'their ends to hold on thc wheels it is an important object to savethe expense of cutting screws by machinery. Inasmuch as both right andleft handed screws are required for this purpose, it involves a heavyoutlay in complicated machinery to pursue the manufacture.

Methods have been contrived by which the male screws on the axle-armshave been molded and east complete; but we are not aware of any planhaving been hitherto practiced by which the female screw hasI beenmolded in sand with sufiicient facility and exactness to obviate theliability of tearing away the sand from the sharp edges of the thread onwithdrawing the pattern, which would render the casting useless.

rBhe object of our invention is to provide a means of molding a nut withits female screwthread complete, so that the nut when cast requires nosubsequent nishing operation, and to perform the operation of moldingwith such facility and rapidity as to materially reduce the cost ofmanufacture.

`Our improvement consists in the use of a plate, a c', adapted to amolding-ask such as is commonly used for similar purposes, which hasformed on and in one piece with it the pattern of the exterior of thenut b. A female screw,c,is formed within it, the exact counterpart ofthe screw required to be cast in the nut. The plate is dividedvertically along the center line, d, and has dowels e e, to cause thetwo halves c c to match exactly when closed together. It also hasparallel grooves f j', which rest on the ridges or guides g g, affixedto the opposite sides of the drag orlower part of the fiask i, and whichserve to guide the two halves of the match-plate a a in placing them onthe fiask, and while withdrawing them laterally from the mold, insuringtheir meeting exactly, and laying flat and parallel when in place.A/cap-plate, k, forms the upper part of the pattern, fitting onto thematched plate by dowels in the corners.

The uses of the several parts will be best understood by describing theprocess of molding a nut. rlhe entire fiask, with the matchplate, cap,&c., in place, as shown in Fig. l, is set on the molding-floor, the gateU print l set up, and the cope or upper part of the flask 7L lled withsand, rammed, and leveled. A board is then placed on it, and the wholeisinverted, with the lower or drag side, i, up.

`The drag is then filled and rammed in like manner, a better quality ofsand being used to fill the core or female screw c, and particular carebeing taken to insure the screw-thread being entirely and perfectlyfilled. The wholev is then restored to its first position, with its copeside up. The cope, with its contained sand, is then lifted off, leavingthe match-plate a a resting on the lower part of the flask. Thecap-plate It is then removed, and the two halves of the match-plate a aare withdrawn by sliding them laterally in opposite directions on theridges g g, thus removing them from the core, and leaving its threadperfect and uninj ured. The cope is then replaced on the drag, the upperand lower surfaces of the sand, before separated by. the thickness ofthe match-plate, now coming together and making a perfect junction. Thetop of the core cnow reaches the top of the impression made by the capK, which is made of the exact thickness of the match-plate a, in orderto occupy the space above the core, which would otherwise be too longwhen the two halves of the mold are closed together. Y

The ask shown in the drawings is provided with hinges m in one ofitscorners, and--is held together by spring-catches n at the oppoflask canbe opened and removed, leaving the y other nuts of the same kind.

site corners. By releasing the Catches n, the

sand mold ready for the reception of the melted metal, while the askvisused for molding It is obvious that many other articles having internalrecesses, the cores of which cannot be removed vertically, may be moldedby similar means, and it is contemplated to apply the invention to otherarticles, which it is unnecessary to enumerate. f

The separate cap-plate k may be dispensed t with in some cases, thoughwe prefer to use it, as shown, when the eore is to reach through 1 thearticle, as in the nut described. l

We do not intend to claim the practice of molding the correspondingparts of a pattern, which are arranged upon the opposite surfaces of aplate interposed between the joining parts of a two-fold iiask, normolding the two halves of the pattern upon separate plates, adapted,

respectively, to the upper and lowerhalves of the mold; but

Vhat we claim, and desire to secure by Letters Patent, is-

The match-plate a c', having both the eXterior and interior of thepattern formed on it, when the same is divided vertically on a centerline, and adapted to a suitable flask, and resting on guides on whichthe two halves of the plate can be Withdrawn laterally in oppositedirections from the eore, substantially as described, for the purpose ofmolding female i screws, or other articles which do not admit of havingthe pattern removed vertically from the core.

EDWARD L. LAMB. sAMUEL woon.

\Vitnesses:

JACOB BUsHEY, J. D. ELLIs.

